The present disclosure relates generally to image processing and more particularly to apparatus and techniques for estimating a velocity field using a sequence of input frames. Computer vision and remote sensing applications often utilize motion field estimation from an image sequence for video coding or other purposes. Conventional velocity estimation techniques include finding a velocity or displacement field using a pair of successive image frames, and existing motion estimation models and algorithms assume that the image intensity recorded from different physical sensors obey a conservation constraint for tracer, heat, or optical flow in space and time. Popular high definition video compression solutions often perform velocity estimation using a block matching algorithm (BMA) in which all pixels of a given block or tile are assumed to be at a constant velocity vector. However, such an assumed velocity field is not continuous at the boundaries between adjacent blocks, leading to poor video reproduction results. Accordingly, there remains a need for improved velocity estimation techniques and apparatus by which improved accuracy and continuous velocity fields is provided with a small set of velocity field parameters to facilitate improved image processing for high ratio video compression and other applications.